具有结构5'UTR的哺乳动物mRNA的翻译启动需要DExH盒蛋白DHX29
Vera P Pisareva1, Andrey V Pisarev, Anton A Komar
1Department of Microbiology and Immunology, SUNY Downstate Medical Center, 450 Clarkson Avenue, Brooklyn, NY 11203, USA.
Cell
|December 27, 2008
概括
有效的真核蛋白质合成需要启动因子DHX29来组装48S复合体在复杂的mRNA结构上. 这种蛋白质有助于解mRNA,对于高效的翻译启动至关重要.
科学领域:
- 分子生物学分子生物学
- 生物化学 生物化学
- 遗传学 是一个遗传学.
背景情况:
- 细胞蛋白质合成开始于mRNA上的48S复合组合.
- 这个过程涉及多个真核细胞启动因子 (eIF) 和43S预启动复合体.
- eIFs 4F,4A和4B解开mRNA的5'-近端区域,帮助复杂的附着和扫描.
研究的目的:
- 研究在具有结构化5'UTRs的mRNA上有效形成48S复合体所需的因素.
- 为了确定参与真核细胞翻译启动的新型蛋白质.
主要方法:
- 生物化学测试用于研究蛋白质-RNA和蛋白质-蛋白质相互作用.
- 在体外分析48S复合物的形成.
- 对DHX29.29的酶活性测定.
主要成果:
- 已知的7个eIF不足以在高度结构化的5'UTR上有效地形成48S复合体.
- 在这个过程中,DEXH盒蛋白DHX29是必不可少的.
- DHX29与40S核糖体子单元结合并水解NTP,其活性由43S复合体刺激.
结论:
- 在翻译启动过程中,DHX29在克服mRNA结构障碍方面发挥着关键作用.
- DHX29的NTPase活性对于促进48S复合物的形成至关重要.
- 这一发现扩大了我们对控制真核转换的分子机制的理解.
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